The keymat is removed at 3:50, while the display unit is already removed.
I can't find it but iirc there was a video some years ago showing some guy casually replacing an N900 keymat in like 30 seconds, without any sort of disassembly except for the keymat bezel.

I have 1x German, 1x Spanish and 1x US. Would gladly swap the German and the Spanish for two US ones.

REQUEST REQUEST REQUEST PLEASE
Could some nice guy post a video on Youtube showing how to swap keymats?
I have a feeling a could do it, but need an easy-to-follow tutorial.
This way I could put the US keymat on my "production" N900 (I've remapped the keyboard, but it's still odd).
THANKS THANKS THANKS THANKS IN ADVANCE

You need: Torx+ (or worst case a Torx, take care to not damage screws with it!) driver size 6, a (unspoiled!) Phillips screwdriver size0(!), ideally use bits when you're unsure about correct torque.
Unscrew the two Torx+ screws left of Shiftkey and right of cursor-right key (see below about pushing out frame via Torx-driver, you can already do that now). Loosen the 4 Phillips screws a 2..3 turns each, do NOT unscrew them! (this step is not strictly needed but helps a lot later on)
Slide open kbd and pull up/out the kbd frame around keymat on bottom long side. If you can't pick it, you can use one of the Torx+ screws, screw it in a 2..3 turns where it been and then press down the screw with the driver, so the frame pops out.
On upper long side you need to swivel out the keybpoard frame, it has a few notches there - to do so you slightly lift the display half from kbd half, that's why you loosened the Phillips screws.
Then swap the keymat, ideally while not removing the frame from its upper notches.
With new keymat in place, you make sure the frame sits tightly and flush in upper notches (slide-push and swivel it into place, use some ruler to make sure it's not bulking up direktion display half, if it does then the notches are not seated correctly) and plug the "forks" at lower long side of frame into the case shell.
Now your new keymat is in place and the frame shall be flush with shell case and not bulk up anywhere above/between "W" and "P".
Gently(!) fix the 4 Phillips and mount the 2 Torx+, using no more force than you can apply using your thumb and index finger fingertips(! no key-grip!) only to turn the screwdrivers/bits on their 3mm diameter metal shaft (actually the correct force/torque is even less than that).

NEVER MIX the two Torx with the Phillips screws - only the Torx may go to the 2 lower side mount positions!

That's a really poor video. It omits a lot of important detailshttps://www.youtube.com/watch?v=43tQws4t2pY is better, however note that you do NOT need to remove the display half, it's also no brilliant idea to do that since you had to mess with the flex cable and the flimsy B2B-connector, and you most likely will damage that flex when all you got for instruction is that tekseven video. Just loosen the 4 Phillips screws holding the display half a 2..3 turns, but do NOT completely unscrew them

The keymat is removed at 3:50, while the display unit is already removed.
I can't find it but iirc there was a video some years ago showing some guy casually replacing an N900 keymat in like 30 seconds, without any sort of disassembly except for the keymat bezel.

That's the (my) issue. I don't want to fully disassemble the N900 just for the keymat. I'll see if I find that video..

EDIT. I'll give it a go with Jörg's instructions. Need to check if I even have the right screwdrivers [I'm really a theoretical engineer. If I told you where I work you'd understand, but I can't..]

I was told that the blackphone team got access to the baseband controller firmware under NDA...

Which doesn't help a thing at all, since a) it's around the size of a standard desktop linux installation, and nobody can check and security-audit all that code, and b) even when they could/would audit it, it can still get updated to a new rogue version OTA

on a short update: Prestashop installed. Pending: configuration (lot of work, mainly for dos1) and import of, and account creation for all our customers, Then we'll send out mails with the URL and credentials

http://neo900.org/donate
(you should "donate" at least 300 Euros to account for the risk part sourcing that's in progress right now [1]).
Alternatively it should be safe to wait for the webshop to go online.